Location: Mosquito and Fly ResearchTitle: Investigating the repellency of trifluoromethylphenyl amides analogues against Aedes aegypti Author
|Tsikolia, Maia - University Of Florida|
|Bernier, Ulrich - Uli|
|Linthicum, Kenneth - Ken|
|Bloomquist, Jeffrey - University Of Florida|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/2/2018
Publication Date: 2/15/2018
Citation: Cuba, I., O'Reilly, E.E., Tsikolia, M., Bernier, U.R., Linthicum, K., Bloomquist, J.R. 2018. Investigating the repellency of trifluoromethylphenyl amides analogues against Aedes aegypti. Meeting Abstract. pg. 1.
Technical Abstract: The purpose of this study is to develop new repellents and evaluate their efficacy for personal protection against mosquitoes. The minimum effective dosage (MED) was determined to estimate the lowest passing concentration of a repellent that prevents >99% of mosquito bites through a treated cloth. DEET (N, N-Diethyl-meta-toluamide) was used as a standard against which to compare new compounds. A total of 27 trifluoromethylphenyl amides analogs (15 of which were chemically novel) containing varying flourine atoms were tested for repellency against adult female Aedes aegypti. Over the past decade, chemicals containing fluorine have become significant in controlling agriculture pests by proving to be effective insecticides and fungicides. Adding fluorines to an aryl ring has demonstrated an increase in lipophilicity and polarizes the parent structure, which may result in an impact on the biological activity of the compounds. There were 3 human volunteers that participated in the repellency bioassay against Aedes aegypti (IRB Project #201602334). Each volunteer wore a latex glove on their hand, a knee-high stocking over their arm, and a plastic sleeve over their entire forearm with a small rectangular cut-out area (4cm x 8 cm). This area allowed for odors from the volunteer’s skin surface to escape and it was the area where the treated cloth was placed. Experimental compounds were dissolved in acetone and serially diluted (highest concentration 1.5mg/cm2). Cloth patches (5cm x 10 cm) were saturated with each dilution and then allowed to dry before starting the bioassay. Individual patches were then laid over the rectangular window on each subject’s arm and then placed into a screened cage (30cm x 30cm x 30cm) containing approximately 500 female mosquitoes, where receiving 0-4 bites is passing and =5 bites results in a failure. None of the trifluoromethylphenyl amide analogues were as effective at repelling Aedes aegypti as currently available DEET. However, compounds 3A (0.031), 6C (0.013), and 6D (0.047) had MED averages closest to DEET (0.005-0.011). Our results show that some trifluoromethylphenyl amides analogues can act as repellents for mosquitoes and could be considered for commercial use to prevent mosquito bites.